Wild Mustard (Sinapis arvensis) is a dicot weed in the Brassicaceae family. In Turkey this weed first evolved multiple resistance (to 2 herbicide sites of action) in 2008 and infests Wheat. Multiple resistance has evolved to herbicides in the Groups B/2, and O/4. These particular biotypes are known to have resistance to dicamba, propoxycarbazone-sodium, thifensulfuron-methyl, triasulfuron, and tribenuron-methyl and they may be cross-resistant to other herbicides in the Groups B/2, and O/4.

The 'Group' letters/numbers that you see throughout this web site refer to the classification of herbicides by their site of action. To see a full list of herbicides and HRAC herbicide classifications click here.

Project Title : Researches on Sulfonylurea Herbicide Resistance in Wild Mustard
Sinapis arvensis L. in Wheat Fields in The Marmara

Region of
Turkey
Start /End Date : 2003-2007

Supporting Body : GDAR

Leader : Muhamet TOPUZ

Co-researchers : Prof. Dr. Yıldız NEMLİ

Summary : Wheat is an important crop for Marmara Region of Turkey. In
wheat fields besides other weeds, wild mustard is also frequent
and important. In wheat growing areas wild mustard is controled
chemically mainly by 2,4-D and sulfonylurea herbicides. It is well
known that heavy usage of sulfonylurea herbicides causes
herbicide resistance. In Marmara Region wheat is grown as a
monoculture or in rotation with vegetables and sunflower where
sulfonylurea usage is also common. With this study it was
determined that wild mustard developed resistance to
sulfonylurea herbicide chlorsulfuron and this is the first report in
Turkey of a broad-leaved weed species, resistant to ALS
inhibitor,resulting from the use of sulfonylureas. Chlorsulfuron
resistant wild mustard populations were tested with some other
sulfonylurea herbicides such as imazamethabenz-methyl,
metsulfuron-methyl, and trifensulfuron, for cross-resistance and
atrazin and 2,4-D for multiple resistance. Chlorsulfuron resistant
populations such as KNF3, KNF4 and MRS6 were found crossresistant
to trifensulfuron, while they were susceptible to all
other applied herbicides. In the management of chlorsulfuron
resistant wild mustard in wheat areas it was concluded that,
herbicides such as 2,4-D, imazamethabenz-methyl, and
metsulfuron-methyl can be recommended as a chemical control
alternatives. Herbicide resistant and susceptible wild mustard
populations were compared for germination and fittness patterns
with aim to obtain information related to the management of
resistance in farmers conditions. Greenhouse, laboratory and
temperature controled growth chamber studies showed that
resistant populations are germinating in high rations compared
to susceptible ones. Molecular studies were conducted with aim
to determine the molecular basis of the mechanism of resistance.
With protein studies total, membrane and soluble proteins
extracted from seed, leaf and rosette stages of wild mustard
resistant and susceptible populations were compared on
proteom level. A significant difference between seed membrane
proteins of wild mustard resistant and susceptible populatıons
were found. DNA studies were conducted as partial ALS gene
sequence of wild mustard resistant and susceptible populations
with aim to find the points of mutations being due to protein
change and resistance.The multiple allighment of sequenced ALS
of resistant and susceptible wild mustard showed that there are
point mutations but not in pro197 and trp 574 which are normally
points where mutations results in amino asit changes. Enzyme
assays showed that in chlorsulfuron resistant populations the ALS
enzyme was not inhibited and that altered target site is the
reason for wild mustard resistance. It was concluded that with full
ALS gene sequence the mutation or mutatıons points can be
found.

Greenhouse trials comparing a known susceptible Wild Mustard biotype with this Wild Mustard biotype have been used to confirm resistance. For further information on the tests conducted please contact the local weed scientists that provided this information.

Genetics

Genetic studies on Group B, O/2, 4 resistant Wild Mustard have not been reported to the site. There may be a note below or an article discussing the genetics of this biotype in the Fact Sheets and Other Literature

Mechanism of Resistance

Studies on the mechanism of resistance of multiple resistant Wild Mustard from Turkey indicate that resistance is due to unknown, and an altered target site. There may be a note below or an article discussing the mechanism of resistance in the Fact Sheets and Other Literature

Relative Fitness

There is no record of differences in fitness or competitiveness of these resistant biotypes when compared to that of normal susceptible biotypes. If you have any information pertaining to the fitness of multiple resistant Wild Mustard from Turkey please update the database.

The Herbicide Resistance Action Committee, The Weed Science Society of America, and weed scientists in Turkey have been instrumental in providing you this information. Particular thanks is given to Çigdem Melike Avci, and F. Nezihi Uygur for providing detailed information.

The discovery of auxinic herbicides (e.g., 2,4-D, Dicamba, Picloram) for selective control of broad-leaf weeds in cereal crops revolutionized modern agriculture. These herbicides are inexpensive and do not generally have prolonged residual activity in soil. Although cultivated species of Brassicaceae (e.g., radish and other vegetables) are susceptible to auxinic herbicides, some biotypes of wild mustard (Sinapis arvensis, 2n=18) were found to be highly resistant to Picloram and Dicamba. Inter-generic hybrids between wild mustard and radish (Raphanus sativus, 2n=18) were produced by traditional breeding coupled with in vitro embryo rescue/ovule culture. To increase frequency of embryo regeneration and hybrid plant production, several hundred reciprocal crosses were performed between these species. Upon altering cultural conditions and media composition, a high frequency of embryo regeneration and hybrid plant establishment was achieved. A protocol was also optimized for in vitro clonal multiplication of inter-generic hybrids produced by embryo rescue. To evaluate transfer of auxinic herbicide resistance from wild mustard into hybrid plants, several screening tests (involving in vitro, molecular-based as well as whole plant-based tests) were performed. Results indicated that hybrids of R. sativus × S. arevensis were resistant to auxinic herbicides suggesting, that, the resistance trait was transferred to these hybrids from the wild mustard. This research for the first time demonstrates the possibility of transfer of auxinic herbicide resistance from wild mustard to radish..

BACKGROUND: Auxinic herbicides are widely used for selective control of many broadleaf weeds, e.g. wild mustard. An auxinic-herbicide-resistant wild mustard biotype may offer an excellent model system to elucidate the mechanism of action of these herbicides. Classical genetic analyses demonstrate that the wild mustard auxinic herbicide resistance is determined by a single dominant gene. Availability of near-isogenic lines (NILs) of wild mustard with auxinic herbicide resistance (R) and herbicide susceptibility (S) will help to study the fitness penalty as well as the precise characterization of this gene. RESULTS: Eight generations of backcrosses were performed, and homozygous auxinic-herbicide-resistant and auxinic-herbicide-susceptible NILs were identified from BC8F3 families. S plants produced significantly more biomass and seed compared with R plants, suggesting that wild mustard auxinic herbicide resistance may result in fitness reduction. It was also found that the serrated margin of the first true leaf was closely linked to auxinic herbicide resistance. Using the introgressed progeny, molecular markers linked to auxinic herbicide resistance were identified, and a genetic map was constructed. CONCLUSION: The fitness penalty associated with the auxinic herbicide resistance gene may explain the relatively slow occurrence and spread of auxinic-herbicide-resistant weeds. The detection of the closely linked markers should hasten the identification and characterization of this gene..

A greenhouse trial has been carried out with different herbicides to prove its efficiency on Sinapis arvensis population suspected to be resistant to tribenuron-methyl. The results confirm that this population survives to all rates of tribenuron-methyl treatments tested. However, this population can be controlled with other family of herbicides, such as 2, 4-D 60% and bromoxinil 12%+ioxinil 12%+mcpp-p 36%..